Ellipsograph



Feb. 2, 1965 A. F. KOMOROWSKI ETAL 3,167,863

ELLIPSOGRAPH 3 Sheets-Sheet 1 Filed April 26, 1963 HENRY A. KOMOEOWSKJ ATToE/vE-Y INVENTO ALEXANDER F. KOMOR0$SKI 1965 A. F. KOMOROWSKI ETAL 3,16

ELLIPSOGRAPH 3 Sheets-Sheet 2 Filed April 26, 1963 INVENTORS ALEXANDER F. KOMOPOWSKI m m .m

BY H EMF-EV A KOMOROWSKI AT TOE/U5 Y 1965 A. F. KOMOROWSKI ETAL 3,

ELLIPSOGRAPH Filed April 26, 1963 5 Sheets-Sheet 3 g 82 as I E W/E V67 8 INVENTORS 28 ALEXANDER F. zomonowsz. Hi-PMEY A. KOMORDWSKI F IG United States Patent 3,167,863 ELLIPSOGRAPH Alexander F. Komorowski and Henry A. Komorowski, both of 69 E. 4th St., Bayonne, NJ. Filed Apr. 26, 1963, Ser. No. 275,890 3 Claims. ((31. 33-30) This invention deals with an ellipsograph. More specifically, it relates to an instrument by means of which it is possible to draw a complete ellipse, once the dimensions of the two main axes are known.

An ellipse can be defined as the parallel projection or shadow of a circle on a plane. When the circle is parallel to the plane depicting its shadow or projection, e.i. when the angle made by the circle with respect to the projection plane is 90, the projection is that of the complete circle. Also, when the angle of the circle is zero with respect to the projection plane, the projection is a straight line. Be tween these two angular positions of the circle, the projection will be an ellipse having a constant major axis and a variable minor axis, depending upon the angle or tilt of the circle with respect to the projection plane.

Heretofore, there have been described in the art various complicated mechanisms for drawing an ellipse, but, as far as is known, there has not been available a simple, easily-operated instrument for drawing a complete ellipse, and one which has no more than two or three moving assemblies.

According to the present invention, a complete ellipse may be readily, conveniently, and simply drawn by use of a graduated frame having a circular slide riding therein, said slide being affixed to one end of an arm, while the other end of said arm rides in a rotatable adjustable pivoted arm. A scriber riding on the graduated arm, then, may be made to circumscribe an ellipse, when the free end of the rotating arm is rotated. Additional features include extending the minor axis limitations of the instrument, as well as providing for an adaptable protractor, as well as other features, which will become apparent from the forthcoming description.

The invention will be more readily understood by reference to the accompanying drawings in which a preferred embodiment having only two moving assemblies is described, and in which FIGURE 1 depicts a top or plan view of an instrument constructed in accordance with the present invention. FIGURE 2 illustrates a front elevational view thereof, with scriber assembly slightly modified. FIGURE 3 shows a cross-sectional top view of a portion of the long arm mounting taken along line 33 of FIGURE 1. FIGURE 4 presents a perspective side view of the finger-rotated knob assembly taken along line 4-4 of FIGURE 1. FIGURE 5 depicts a crosssectional perspective front view of the scriber slide assembly, partly cut away and partly in exploded form, taken along line 5-5 of FIGURE 1. FIGURE 6 illustrates a cross-sectional side view of the center line slide and part of the adjacent frame members, taken along line 6--6 of FIGURE 1. FIGURE 7 shows a cross-sectional side view of the scriber slide locking mechanism taken along line 7-7 in FIGURE 1. FIGURE 8 presents a perspective top view of a protractor which is useable with the ellipsograph of the present invention for maintaining the ellipsograph at a desired angle. Similar numerals refer to similar parts in the various figures.

Referring again to the drawings, numeral 8 indicates generally a frame, preferably rectangular in shape, and preferably made of transparent plastic. Frame 3 has front 9, back 10, and sides 11 and 12, and it is supported by legs 13, 14, 15 and 16. The inner edges 17 and 18 of frame members 9 and 10, respectively, are provided with grooves or races 19 and 20, respectively, in which slide rounded edges 21 and 22 of slide end portion 23, also 3,167,853 Patented Feb. 2, 1965 ice preferably made of transparent plastic. Arcuate edges 22 and 21 must have a common diameter.

Attached to slide end 23 by screws 24 is flat slide scale 25, also preferably made of transparent plastic. This scale is graduated for the minor diameter of the ellipse desired, e.g., by degrees of angle of tilt 26. Scale 25 has forwardly-projecting ends 25 and 25" between which are mounted slide rods 27 and 28, and on which slides the scriber assembly generally indicated by numeral 29. Scale 26 is raised by leg 52 (FIG. 2), and extends laterally above the plane of frame 8.

Scriber slide assembly 29 consists of upper mounting 30 and lower mounting 31, the latter being joined (via screws 38) by a vertical connector 32, the bottom of which is hinged to lower mounting 31 by hinge 33. Upper mounting 30 consists of slide 34 carrying scriber 35, the scriber elevation control indicated generally by numeral 36, and the slide locking mechanism, indicated generally by numeral 37. As shown in FIGURE 5, scriber 35 is inserted or screwed into hollow knob 39, and it has pencil scribing point for drawing the ellipse. The pencil may be substituted by a metal scriber, or the like, depending on the material on which the ellipse is to be drawn and the type of scribing desired. Sleeve 41, which is mounted on slide plate 34, holds scriber knob 39, and is provided on its upper edge with notches 42 and 43, of different height, for rough elevational positioning of scriber point 40. Pin 44 in the side of knob 39 serves as a stop and positioner in the notches. More accurate tension control of scriber point 40 on the surface to be scribed can be obtained by means of tension control 36. Here, flat spring 45 is mounted on one end to the bottom of plate 34 by means of screw 46. The other end of spring 45 is positioned in slot 47 in the side of knob 39. Knobbed screw 48 penetrates plate 34 and its end impresses a thrust on the center portion of spring 45, thereby enabling adjustment of the tension of the scriber when desired to attain the proper scribing pressure on point 40. Plate 34 also carries, at its uppermost edge, a line mark 88 which is used together with scale 26 on slide 25, to set the instrument for the minor axis of the ellipse to be drawn.

Lower scriber mounting 31 consists of an arm 51 hinged at 33 to connector 32, so that it extends laterally below the plane of frame 8, while plate 34, in turn, extends laterally in a plane above that of frame 8. Arm 51 terminates at its free end with an auxiliary scriber having point 53 in vertically-adjustable screw 54. The distance between scriber points 40 and 53 is fixed, such as 30 of (circle) tilt, as will be explained later. Fastened on arm 51, near hinge 33, is vertically-projecting pin 55 which can lock in notches 55' or 56 on the end of plate 34, and serves to lock arm 51 in raised position (notch 55') or lowered position (notch 56). The rearward portion of plate 34 also has an indicator line or arrow 88 near the, edge which enables the aligning of the scriber assembly with angle markings 26 on scale 25 to position the instrument with respect to the minor diameter of the ellipse to be drawn.

Plate 34 may be locked in position by mechanism 37, as shown in FIGURE 7. Here, knobbed screw 49 penetrates plate 34 at a point midway between slide rods 27 and 28. Plastic nut on screw 49 spans both rods so that, when the screw is tightened, the nut 50 presses rods 27 and 28 against the bottom of plate 34 and thus locks the plate in position.

The forward member 9 of frame 8 has a scale 58 on its rearward edge to mark the length of the major axis of the ellipse desired. Marking 59 on are portion 21 of slide end 23 is used in cooperation with markings 58 on frame member 9 for obtaining the major diameter setting of the ellipse.

Disposed between forward legs 13 and 16 of the frame is slide rod 60 on which rides centerline slide 61 bearing 7 line marking 62. As can be seen from FIGURE 6, center line slide 61 is disposed below the other elements of the instrument and is preferably at or near the plane of the material on which the scribing is to take place. It is preferredthat the forwardportion of front frame member 9 be cut out to provide open space 63, to facilitate viewingcenter line slide 61 from the top. The use of the center line slide will be outlined later.

Attached to the middle of right frame member 12 at pivot 64 (at its one end) is short rotating arm .65 having groove 66 cut. lengthwise its upper surface. Tenon 67 slides engageably in groove 66 (FIG. 4), and the latter is held by screw 68 terminating in knob '69 which has a hollowed center 70 in which a finger may be inserted for motivation. An upper binding plate 71 is mounted on screw 68 over arm 65 (for facilitating the locking of the assembly) and, above plate 71, is fitted (also over screw 68) the end 25" of scale plate 25 (via bushing 72). From theforegoing, it can be seen that when knob 69is screwed down tight, tenon 67 is locked tightly against binding plate 71, but end 25" is free to move around bushing 72 as arm 65 is rotated around pivot 64 (FIG. 1).

In FIGURE 8, a protractor is shown which may be used to facilitate positioning and drawing of the ellipse. Protractor plate 84 hearing the angle scale 90 has two forward corner holes 82 and 83 whichfit over legs 13 and 14, respectively, of the ellipsograph frame. The movable plate 85 is pivoted at 86 to plate 84 and it has straight edge 87 for the aligning operation, as will be hereinafter explained. Stop arm 80 is swivelly mounted on one end to back of the frame and is designed to prevent rotation of arm .65, thus enabling the holding of scale arm in parallel alignment with short arm 65 for line-up of the ellipse to be drawn.

It will be noted that when arms 25 and 65 are in lineup position by abutting stop 80, scriber points and 53 are centrally-disposed in the vertical direction within frame 8, and they are in straight line alignment with pivot 64.

The ellipsograph of the present invention is used as follows: First, it is necessary that both scriber points 40 and 53 be raised so as to be out of contact with the paper or other surfaceon which the ellipse is to be drawn. This is done by turning knob '39 until pin 44 is in upper notch 43, for example, and pin is locked in outermost notch 55.

Next, the. protractor is employed for drawing the center line of the ellipse on the surface. This is done by laying a T-square across the surface (on a drawing board) on which the ellipse is to be drawn, and then placing the protractor on the T-square edge and drawing the center line (minor. axis). Thereafter, legs 13 and 14 of the ellipsograph are inserted into holes 82 and 83, respectively, of the protractor, and arm 85 of the protractor is turned on pivot 86 and below front 9 on the drawing board and setting the angle of the protractor on scale 90 to coincide with theangle of the center line of the ellipse. When this is done, lateral movement of the ellipsograph with. edge 84 of the protractor abutting the T-square will keep the ellipsograph at the same angle as the drawn center line.

The next step is tomove center line slide 61 until the center line indicator 62 is immediately above the drawn center line of the ellipse, thereby making it a simple matter to position the ellipsograph with respect to the drawn center line.

Then, thesetting must be made for the length of the minor axis. This is accomplished by loosening knob 49 until plate 34 is free to ride on rods 27 and 28, and sliding plate 34 until indicator 88, is in line with the desired angle of tilt on marks 26 of scale 25. Thereafter, knob49 istightened so as to lock plate 34 in place.

Next, line-up stop 80 is turned on its swivel 81 (FIG. 1) until stop arm 80 is at right angles to grooved arm 65, and both arms are in contact, thus placing the instrument in line-up position! Next, the knob 69 on rotatable arm 65 is loosened and is moved in groove 66 until the desired major diameter length reading is obtained on scale 58 via marker 59, and knob 69 is tightened. After this is done, the ellipsograph is moved laterally along'th'e T-square until the center line marking 62 is in juxtaposition with the drawn center line on the paper. Then, writing point 40 isdropped in ploce on the working center line of the drawing, by moving pin 44 into lower notch 42 of the scriber, and the desired tension'of point 40 on the paper surface is adjusted via knob 48.

The instrument now is ready for drawing of the ellipse. This is done by moving stop out'of the way, placing the index finger in thehollow of'knob 69 and rotating the assembly around pivot 64, while holding frame 8 stationary. A complete ellipse having the desired dimensions is thus drawn, up to a tilt angle (minor axis) of 60.

If a minor axis greater than 60 of tilt isdesired, use is made of auxiliary stylus orscriber 53. In this case, the length of arm 51 from scriber 40 to scriber 53 is exactly 30 of tilt, which means that when scriber 53 is used, instead of scriber 40, a-figure of 30 must be added to the reading of minor axis scale 26. Thus, if a ellipse (or complete circle) is to be drawn, scriber 40 is raised and scriber 53 is lowered by slipping pin 55 out of notch 55 and into notch 56(as in FIG. 1). Then, the ellipsograph is manipulated as previously outlined, except that whenplate 34 is locked so that marker 88 is in line with 60 on scale 25, the minor diameterreading actually will be 90, so that, when arm 65 is turned by means of knob 69, scriber 53 will circumscribe a circle.

Although the drawings illustrate an ellipsograph in which the slide moves in an are as the scale arm reciprocates, it is-also apparent that the slide can be made to reciprocate only, while. the scale arm may be pivoted thereon for obtaining the arcuate motion of the scriber. The essentialfeature, however, is the fact that both slide and arm must reciprocate, as required, while one ofthese elements must follow the arcuate motion generated by rotation of the rotating arm.

Unless otherwise specified, all parts, wherever possible, are made of transparent plastic.

We claim:

1. An ellipsograph for drawing, on a surface, a complete ellipse having a major and a minor axis, comprising,

a frame having a front, back, and sides, and having slide-engaging means at the inner edges of said front and back,

a slide movablewithin said frame near one side thereof between said slide engaging means, and designed to turn and reciprocate therein,

a scale arm carrying a minor axis scale and attached at one end to and above said slide in a manner such that saidslidel and scale ar-nr are movable freely as a unit as the hereinafter-mentionedrotating arm is rotated, said scale arm projecting toward the opposite frame side,

a rotating arm swivably attached at its one end to the middle of the top of said opposite frame side and having slide-engaging means thereon,

swivel engaging means disposed on the other end of said scale arm designed to engage in slidable and rotatable relation with the slideaengagingmeans on said rotating arm, 9 V

knob locking means for locking said other scale arm end in said latter slide-engaging means-while said connected rotating armis free to rotate,

a plate slidably engaged to said scale arm and carrying an indicator and designed to slide in parallel relation with and adjacent .to said scale arm,

a vertically-adjustable scriber mounted in downwardly directed relation on said plate in a manner such that when saidscale arm is positioned in parallel relation with said rotating arm, the scriber is disposed within the center area of" said frame, a

a marking on said slide adjacent one of the sliding edges,

a major axis scale disposed on the frame member adjacent said slide marking in a manner such that when said plate is slid so that its marking is opposite the desired minor axis reading on said scale arm and the marking on the slide is opposite the desired major axis marking on said frame, and said knob is locked, rotation of said knob, while the scriber is in contact with a surface, will draw an ellipse having the desired dimensions,

a ce-nterline slide attached to a non-side frame member,

and

a marker disposed on said latter slide for spotting the center line of an ellipse to be drawn.

2. An ellipsograph for drawing, on a surface, a complete ellipse having a major and a minor axis, comprising,

a frame having a front, back, and sides, and having slide-engaging means at the inner edges of said front and back,

a slide movable within said frame near one side thereof between said slide engaging means, and designed to turn and reciprocate therein,

a scale arm carrying a minor axis scale and attached at one end to and above said slide in a manner such that said slide and scale arm are movable freely as a unit as the hereinafter-mentioned rotating arm is rotated, said scale arm projecting toward the opposite frame side,

a rotating arm swivably attached at its one end to the middle of the top of said opposite frame side and having slide-engaging means thereon,

swivel engaging means disposed on the other end of said scale arm designed to engage in slidable and rotatable relation with the slide-engaging means on said rotating arm,

knob locking means for locking said other scale arm end in said latter slide-engaging means while said connected rotating arm is free to rotate,

a plate slidably engaged to said scale arm and carrying an indicator and designed to slide in parallel relation with and adjacent to said scale arm,

a vertically-adjustable scriber mounted in downwardlydirected relation on said plate in a manner such that when said scale arm is positioned in parallel relation with said rotating arm, the scriber is disposed within the center area of said frame,

a marking on said slide adjacent one of the sliding edges,

a major axis scale disposed on the frame member adjacent said slide marking in a manner such that when said plate is slid so that its marking is opposite the desired minor axis reading on said scale arm and the marking on the slide is opposite the desired major axis marking on said frame, and said knob is locked, rotation of said knob, while the scriber is in contact with a surface, will draw an ellipse having the desired dimensions,

legs disposed under said frame and designed to raise said frame above a drawing surface, and,

a protractor .plate having holes therein designed to permit fitting therein of at least two legs on said frame, said protractor having a straight edge attached in .swivelling arrangement with the protractor scale to permit alignment thereof with a straight edge for maintaining said ellipsograph at the same angle as that of the center line of an ellipse to be drawn.

3. An ellipsograph for drawing, on a surface, a complete ellipse having a major and a minor axis, comprising,

a frame having a front, back, and sides, and having slide-engaging means at the inner edges of said front and back,

a slide movable within said frame near one side thereof between said slide engaging means, and designed to turn and reciprocate therein,

a scale arm carrying a minor axis scale and attached at one end to and above said slide in a manner such that said slide and scale arm are movable freely as a unit as the hereinafter-mentioned rotating arm is rotated, said scale arm projecting toward the opposite frame side,

a rotating arm swivably attached at its one end to the middle of the top of said opposite frame side and having slide-engaging means thereon,

swivel engaging means disposed on the other end of said scale arm designed to engage in slidable and rotatable relation with the slide-engaging means on said rotating arm,

knob locking means for locking said other scale arm end in said latter slide-engaging means while said connected rotating arm is free to rotate,

a plate slidably engaged to said scale arm and carrying an indicator and designed to slide in parallel relation with and adjacent to said scale arm,

a vertically-adjustable scriber mounted in downwardlydirected relation on said plate in a manner such that when said scale arm is positioned in parallel relation with said rotating arm, the scriber is disposed within the center area of said frame,

a marking on said slide adjacent one of the sliding edges,

a major axis scale disposed on the frame member adjacent said slide marking in a manner such that when said plate is slid so that its marking is opposite the desired minor axis reading on said scale arm and the marking on the slide is opposite the desired major axis marking on said frame, and said knob is locked, rotation of said knob, while the scriber is in contact with a surface, will draw an ellipse having the desired dimensions,

legs disposed under said frame and designed to raise said frame above a drawing surface,

a vertically-movable scriber arm disposed under said plate and hingeably mounted at its one end with respect to the plate side adjacent said near frame side and having its other end extending laterally past said scriber toward said opposite frame side,

a downwardly-directed auxiliary scriber mounted on said other end of said scriber arm, the distance between said both scribers being in predetermined relation with the scale on said scale arm, and

locking means for locking said scriber arm in raised position out of contact with a drawing sunface.

12/57 France.

4/ 13 Germany. 2/ 48 Great Britain.

ISAAC LISANN, Primary Examiner.

ROBERT B. HULL, Examiner. 

1. AN ELLIPSOGRAPH FOR DRAWING, ON A SURFACE A COMPLETE ELLIPSE HAVING A MAJOR AND A MINOR AXIS, COMPRISING, A FRAME HAVING A FRONT, BACK, AND SIDES, AND HAVING SLIDE-ENGAGING MEANS AT THE INNER EDGES OF SAID FRONT AND BACK, A SLIDE MOVABLE WITHIN SAID FRAME NEAR ONE SIDE THEREOF BETWEEN SAID SLIDE ENGAGING MEANS, AND DESIGNED TO TURN AND RECIPROCATE THEREIN, A SCALE ARM CARRYING A MINOR AXIS SCALE AND ATTACHED AT ONE END TO AND ABOVE SAID SLIDE IN A MANNER SUCH THAT SAID SLIDE AND SCALE ARM ARE MOVABLE FREELY AS A UNIT AS THE HEREINAFTER-MENTIONMED ROTATING ARM IS ROTATED, SAID SCALE ARM PROJECTING TOWARD THE OPPOSITE FRAME SIDE, A ROTATING ARM SWIVABLY ATTACHED AT ITS ONE END TO THE MIDDLE OF THE TOP OF SAID OPPOSITE FRAME SIDE AND HAVING SLIDE-ENGAGING MEANS THEREON, SWIVEL ENGAGING MEANS DISPOSED ON THE OTHER END OF SAID SCALE ARM DESIGNED TO ENGAGE IN SLIDABLE AND ROTATABLE RELATION WITH THE SLIDE-ENGAGING MEANS ON SAID ROTATING ARM, KNOB LOCKING MEANS FOR LOCKING SAID OTHER SCALE ARM END IN SAID LATTER SLIDE-ENGAGING MEANS WHILE SAID CONNECTED ROTATING ARM IS FREE TO ROTATE, A PLATE SLIDABLY ENGAGED TO SAID SCALE ARM AND CARRYING AN INDICATOR AND DESIGNED TO SLIDE IN PARALLEL RELATION WITH AND ADJACENT TO SAID SCALE ARM, A VERTICALLY-ADJUSTABLE SCRIBER MOUNTED IN DOWNWARDLYDIRECTED RELATION ON SAID PLATE IN A MANNER SUCH THAT WHEN SAID SCALE ARM IS POSITIONED IN PARALLEL RELATION WITH SAID ROTATING ARM, THE SCRIBER IS DISPOSED WITHN THE CENTER AREA OF SAID FRAME, A MARKING ON SAID SLIDE ADJACENT ONE OF THE SLIDING EDGES, A MAJOR AXIS SCALE DISPOSED ON THE FRAME MEMBER ADJACENT SAID SLIDE MARKING IN A MANNER SUCH THAT WHEN SAID PLATE IS SLID SO THAT ITS MARKING IS OPPOSITE THE DESIRED MINOR AXIS READING ON SAID SCALE ARM AND THE MARKING ON THE SLIDE IS OPPOSITE THE DESIRED MAJOR AXIS MARKING ON SAID FRAME, AND SAID KNOB IS LOCKED, ROTATION OF SAID KNOB, WHILE THE SCRIBER IS IN CONTACT WITH A SURFACE, WILL DRAW AN ELLIPSE HAVING THE DESIRED DIMENSIONS, A CENTERLINE SLIDE ATTACHED TO A NON-SIDE FRAME MEMBER, AND A MARKER DISPOSED ON SAID LATTER SLIDE FOR SPOTTING THE CENTER LINE OF AN ELLIPSE TO BE DRAWN. 